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基于AquaCrop模型的水稻多目标灌溉制度优化研究

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灌溉排水学报 2024年第1期43卷 9-16页

作者：马超吴天傲章伟忠李江缴锡云河海大学农业科学与工程学院南京211100 河海大学水文水资源与水利工程科学国家重点实验室南京210098 水科学与水安全协同创新中心南京210098 常熟市水利工程质量监督站江苏苏州215500

【目的】优化现有水稻灌溉制度,节约灌溉用水量,减少稻田氮磷流失量以降低面源污染风险。【方法】构建了基于AquaCrop模型和NSGA-Ⅱ算法的水稻灌溉制度模拟优化模型,利用水稻田间试验数据,开展以产量最大、氮磷流失量最小、灌水次数最少... 详细信息

【目的】优化现有水稻灌溉制度,节约灌溉用水量,减少稻田氮磷流失量以降低面源污染风险。【方法】构建了基于AquaCrop模型和NSGA-Ⅱ算法的水稻灌溉制度模拟优化模型,利用水稻田间试验数据,开展以产量最大、氮磷流失量最小、灌水次数最少的3种目标组合(产量-氮磷流失量(Y-TNP)、产量-灌水次数(Y-N)、产量-氮磷流失量-灌水次数(Y-TNP-N))下的灌溉制度优化模型研究,提出适应不同生育期降水年型的稳产-控污-提效灌溉制度。【结果】(1)与常规灌溉相比,Y-TNP灌溉制度优化水稻产量下降2.14%,氮磷流失量减少23.09%;Y-N灌溉制度优化水稻产量下降1.76%,灌水次数减少53%;Y-TNP-N灌溉制度优化水稻产量下降2.64%,氮磷流失量减少22.83%,灌水次数减少2次。(2)不同典型年以Y-TNP-N为目标优化的稳产-控污-提效灌溉制度水稻产量介于7.74~7.78 t/hm^(2),同时大幅度减少灌水量进而降低氮磷流失量。【结论】AquaCrop模型可模拟试验区水稻的生长发育过程,本文构建的模拟-优化耦合模型可用于优化不同生育期降水年型下稳产-控污-提效的灌溉制度。

关键词：水稻灌溉制度 AquaCrop模型 NSGA-Ⅱ优化算法面源污染

Multispecies coalescent and its applications to infer species phylogenies and cross-species gene flow

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National Science Review 2021年第12期8卷 86-103页

作者： xiyun jiao Tomá■ Flouri Ziheng Yang Department of Genetics Evolution and EnvironmentUniversity College London Department of Statistics and Data Science Southern University of Science and Technology

Multispecies coalescent(MSC) is the extension of the single-population coalescent model to multiple species. It integrates the phylogenetic process of species divergences and the population genetic process of coalescent, and provides a powerful framework for a number of inference problems using genomic sequence data from multiple species, including estimation of species divergence times and population sizes,estimation of species trees accommodating discordant gene trees, inference of cross-species gene flow and species delimitation. In this review, we introduce the major features of the MSC model, discuss full-likelihood and heuristic methods of species tree estimation and summarize recent methodological advances in inference of cross-species gene flow. We discuss the statistical and computational challenges in the field and research directions where breakthroughs may be likely in the next few years.

关键词： anomaly zone BPP deep coalescence gene flow Markov chain Monte Carlo multispecies coalescent species tree

秸秆还田及过程因素对土壤氮素影响的Meta分析

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灌溉排水学报 2024年第7期43卷 93-97页

作者：黄增健李江缴锡云郭维华顾哲河海大学农业科学与工程学院南京211100 河海大学水安全与水科学协同创新中心南京210098 河海大学水灾害防御全国重点实验室南京210098

【目的】评估秸秆还田过程中不同因素对农田土壤氮素水平的影响。【方法】基于Meta分析,在中国知网、Web of Science及Science of Direct搜集秸秆还田文献42篇,共得到314对数据,量化秸秆种类、土壤初始条件、秸秆还田方式、秸秆还田量... 详细信息

【目的】评估秸秆还田过程中不同因素对农田土壤氮素水平的影响。【方法】基于Meta分析,在中国知网、Web of Science及Science of Direct搜集秸秆还田文献42篇,共得到314对数据,量化秸秆种类、土壤初始条件、秸秆还田方式、秸秆还田量、氮肥配施量以及秸秆还田年限对土壤氮素水平的影响。【结果】不同种类秸秆还田均能够提高土壤总氮量;相比黏土,秸秆还田更有利于促进砂土和壤土的氮素积累;在碱性土壤条件下进行秸秆还田,土壤固氮效果较好;秸秆还田后土壤氮素提升率随土壤碳氮比的增加而下降;采用翻耕、旋耕和免耕进行秸秆还田分别提升了9.11%、7.84%、5.34%的土壤总氮量;秸秆还田过程中少量(≤150 kg/hm^(2))和中量(150~250 kg/hm^(2))配施氮肥条件下的土壤固氮效果较为接近,氮肥施用量˃250 kg/hm^(2)时,土壤氮素积累效果显著提升;长期秸秆还田(>10 a)与短期秸秆还田(1~4 a)取得的土壤增氮效果接近。【结论】碱性、低碳氮比的非黏性土壤更有利于秸秆腐解及氮素释放,为促进土壤氮素积累,建议在合理配施氮肥条件下将秸秆以翻耕的方式进行中短期(≤10a)还田。

关键词：秸秆还田土壤氮素 Meta分析

Simulating advance distance in border irrigation systems based on the improved method of characteristics

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International Journal of Agricultural and Biological Engineering 2021年第3期14卷 156-162页

作者： Kaihua Liu xiyun jiao Weihua Guo Mohamed Khaled Salahou Zhe Gu College of Hydrology and Water Resources Hohai UniversityNanjing 210098China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing 210098China College of Agricultural Science and Engineering Hohai UniversityNanjing 210098China Cooperative Innovation Center for Water Safety and Hydro Science Hohai UniversityNanjing 210098China

Improving the simulation accuracy of the advance distance based on the method of characteristics is essential to develop numerical solutions for simulating surface *** of volume balance in the traditional method of characteristics(T-MC),the position of critical flow is determined to simulate the advance distance in the improved method of characteristics(I-MC),which is used in border irrigation systems with rapid variation in inflow discharge in the current ***,the zones of both subcritical and supercritical flow were firstly distinguished to determine the position of the critical flow point,which was also the upstream boundary of the wetting front region,and then the advance distance was calculated by applying the diffusive wave equation in the wetting front *** results showed that the I-MC accurately simulated the advance distance with high determination coefficients(0.984-0.998)and low errors(root mean square error of 0.35-1.56 min and coefficient of residual mass of 0.01-0.06),which performed much better than the *** I-MC provided a suitable and simple numerical simulation tool to improve the establishment of numerical surface irrigation models.

关键词： border irrigation numerical solution advance distance method of characteristics

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泡田期稻田养分流失特征与回用效果分析

灌溉排水学报 2024年第10期43卷 106-113页

作者：王星朗巫纾予刘凯华缴锡云王欣河海大学农业科学与工程学院南京211100 水灾害防御全国重点实验室南京210098 南京市长江河道管理处南京210011

[目的]揭示太湖地区泡田期田-沟-河灌排系统稻田养分流失特征及其在尾水回用下养分拦截回用比例及效果。[方法]基于原位试验记录各级灌排单元中的水量、水质,分析泡田期稻田养分流失特征,选用熵权法计算各指标权重,识别各级灌排单元的... 详细信息

[目的]揭示太湖地区泡田期田-沟-河灌排系统稻田养分流失特征及其在尾水回用下养分拦截回用比例及效果。[方法]基于原位试验记录各级灌排单元中的水量、水质,分析泡田期稻田养分流失特征,选用熵权法计算各指标权重,识别各级灌排单元的关键水质因子,并结合水量、水质数据计算尾水回用格局下各水质因子的回用率。[结果]泡田期内各指标浓度在田-沟级呈先升高后降低的趋势,而河道级延后1~2 d后升高,泡田结束时均高于初始水平,各水质指标浓度随水流流向呈梯级递减趋势。田-沟级关键水质因子为氮,随水流至河道级后转变为化学需氧量(COD)。在尾水回用格局下,总回用水量达到泡田定额的45.56%,总氮(TN)、铵态氮(NH_(4)^(+)-N)、总磷(TP)、COD回用率分别达到51.96%、33.68%、57.61%、42.65%。[结论]泡田期灌溉定额大,稻田养分流失风险高,通过尾水回用可有效减少泡田定额,并将稻田排水中的养分回归入田以降低污染物外排风险。本研究有助于从灌排单元尺度上提高节水、减排水平,助力太湖地区农业可持续发展。

关键词：泡田期面源污染养分流失尾水回用

Performance of a zero-inertia model for irrigation with rapidly varied inflow discharges

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International Journal of Agricultural and Biological Engineering 2020年第2期13卷 175-181页

作者： Kaihua Liu xiyun jiao Jiang Li Yunhao An Weihua Guo Mohamed Khaled Salahou Honghui Sang State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China College of Agricultural Engineering Hohai UniversityNanjing 210098China Cooperative Innovation Center for Water Safety and Hydro Science Hohai UniversityNanjing 210098China

The zero-inertia model is widely used for simulating surface flow in irrigation *** model is accurate when inflow discharge is ***,simulation of irrigation systems with rapidly varied inflow discharge is needed due to the development of real time control irrigation ***,the objective of this study is to validate the zero-inertia model with rapidly varied inflow *** this purpose,twenty-three border irrigation tests at a range of inflow changes on different field slopes and roughness coefficients were ***,the sensitivity analyses of bed slope,infiltration parameters,and roughness coefficient were *** results indicate that the zero-inertia model predictions are in good agreement with field data in both advance/recession times and flow *** infiltration parameters were the most sensitive input variable of the zero-inertia *** input variables have a more considerable impact on the recession phase than the advance phase.

关键词： zero-inertia model rapidly varied inflow border irrigation sensitivity analysis

Effects of regulated deficit irrigation on soil salinity,physiological processes and fruit quality of gray jujube under desert conditions

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International Journal of Agricultural and Biological Engineering 2019年第3期12卷 52-59页

作者： Zhipeng Liu Chengli Zhu Shuyu Wu Weihua Guo Yitikaer Abudushalamu xiyun jiao Shipei Gao Jie Wang College of Agricultural Engineering Hohai UniversityNanjing 210098China College of Hydraulic and Civil Engineering Xinjiang Agricultural UniversityUrumqi 830052China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China Hydraulic Research Institute of Jiangsu Province Nanjing 210017China Development Center for Science and Technology of Rural Water Resources of Jiangsu Province Nanjing 210029China

Regulated deficit irrigation(RDI)was applied to gray jujube trees in an oasis region,to determine the effects of this irrigation system on soil salinity,gray jujube physiological processes,fruit yield,and fruit *** consisted of severe,moderate and low deficit irrigation(irrigated with 85%,70%and 55%of CK,respectively)at the flowering stage to fruit set *** the other growth stages,all treatments were irrigated with 80%of pan evaporation,which was the same as that in *** results indicated that soil salinity was enhanced during the periods of water stress,but the high value of soil salinity declined by 3.48%-37.27%,at each depth,after irrigation was *** caused a decline in the photosynthetic rate,transpiration rate,and stomatal conductance,but enhanced the water use efficiency of the ***,the leaf photosynthetic rate was effectively enhanced after the recovery of irrigation,especially in the moderate deficit irrigation treatment,which exceeded the *** led to an improved fruit yield,which was 9.57%higher than that of the *** deficit treatments caused a significant increase in the soluble solid content,soluble sugar content,single fruit weight and sugar/acid *** vitamin C content,resulting from deficit treatments,has also been observed in the gray ***,this research shows that RDI provides some benefits in the production of gray jujube trees in desert conditions.

关键词： regulated deficit irrigation soil salinity gray jujube water use efficiency photosynthetic rate transpiration rate stomatal conductance soluble solid content sugar/acid ratio

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MICP加固土质排水沟边坡稳定性分析

灌溉排水学报 2024年第5期43卷 71-78页

作者：罗丹虎缴锡云巫纾予刘凯华郭维华李焕弟河海大学农业科学与工程学院南京211100 河海大学水文水资源学院南京210098

【目的】探究应用微生物诱导CaCO3沉淀(MICP)固结土壤技术对于土质排水沟边坡稳定性的影响机制。基于土工直剪试验和数值模拟法研究不同工况下MICP加固的土坡稳定性,为MICP生物护坡措施应用于土坡加固提供理论依据。【方法】选用OD600=0... 详细信息

【目的】探究应用微生物诱导CaCO3沉淀(MICP)固结土壤技术对于土质排水沟边坡稳定性的影响机制。基于土工直剪试验和数值模拟法研究不同工况下MICP加固的土坡稳定性,为MICP生物护坡措施应用于土坡加固提供理论依据。【方法】选用OD600=0.97的巴氏芽孢杆菌和1 mol/L的固结液(CO(NH_(2))_(2)∶CaCl_(2)=1∶1),固菌比为5∶3,添加15%固结液质量的脲酶抑制剂。布置4个试验土箱,设置对照组CK和固结组C1、C2、C3,对照组喷洒清水,设计入渗10 cm土层,固结组按先固结液后菌液顺序喷洒设计入渗5、10、15 cm土层。对固结后的风干土、饱和土、落干土进行直剪试验,利用直剪结果分析不同工况土坡稳定性。【结果】MICP处理的土体抗剪强度均有所提升;饱和处理后CK、C1、C2、C3的内摩擦角降幅为46.67%,39.73%,28.98%和27.85%,黏聚力降幅76.37%,62.83%,39.09%和51.62%,CK土坡处于欠稳定,C1、C2、C3土坡满足安全要求,黏聚力是影响边坡稳定的主要因素。【结论】MICP可以提高土质排水沟边坡的稳定性,其最佳固结深度是10 cm。

关键词： MICP固结土质边坡固结深度边坡稳定

Tomato and cowpea crop evapotranspiration in an unheated greenhouse

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Water Science and Engineering 2008年第2期1卷 112-120页

作者： Xu Junzeng Peng Shizhang Luo Yufeng jiao xiyun State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering College of Water Resources and Environment Hohai University Nanjing 210098 P. R. China Institute of Water-Saving Irrigation Hohai University Nanjing 210098 P. R. China

With the development of protected cultivation of vegetables in China, it is necessary to study the water requirements of crops in greenhouses. Lysimeter experiments were carried out to investigate tomato （2001） and cowpea （2004） crop evapotranspiration （ETc） in an unheated greenhouse in Eastern China. Results showed remarkably reduced crop evapotranspiration inside the greenhouse as compared with that outside. ETc increased with the growth of the crops, and varied in accordance with the temperature inside the greenhouse and 20-cm pan evaporation outside, reaching its maximum value at the stage when plants’ growth was most active. Differences between the variation of crop evapotranspiration and pan evaporation inside the greenhouse were caused by shading of the pan in the later period when the crops were taller than the location where the pan was installed, 70 cm above ground. The ratio of crop evapotranspiration to pan evaporation was not constant as reported in previous studies, and the variation of the inside ratio αin lagged behind that of the outside ratio αout. Simulation of crop evapotranspiration based on 20-cm pan evaporation inside the greenhouse is more reasonable than that based on 20-cm pan evaporation outside, although pan evaporation outside is more consistent with ETc than that inside. The value of αin, calculated based on air temperature, relative humidity, and ground temperature inside, plays a dominant role in the calculation of ETc. As the crop height increases, altering the location of the inside pan and placing it above the canopy, out of the shade, would help to achieve more reasonable values of crop evapotranspiration.

关键词： crop evapotranspiration pan evaporation unheated greenhouse tomato cowpea